So, I really can’t recommend for upgrading yet. Fedora 9 seems to be stuffed too much beta and pre-release versions.

Edit: Firefox 3 is released and available.

Edit: Upgraded the nVidia Quadro4 380 XGL to nVidia GeForce6200 512MB (cost 42 €) to get the 173.14.09 drivers working (+ compiz now works with dual head too). Also 96.43.07 drivers are now available, but not tested here.

Edit: All the flaws have been worked around, and the Fedora 9 upgrade is recommended.